Unit:
Κατεύθυνση ΑστροφυσικήLibrary of the School of Science
Author:
Chatzis Margaritis
Supervisors info:
Μαρία Πετροπούλου, Επίκουρη Καθηγήτρια, Τμήμα Φυσικής, ΕΚΠΑ
Original Title:
A study of broadband variability in the context of hybrid leptohadronic models for TeV blazars
Translated title:
A study of broadband variability in the context of hybrid leptohadronic models for TeV blazars
Summary:
Blazars – a subclass of active galaxies – are intrinsically time-variable broadband sources of
electromagnetic radiation. While modeling their time-average spectral energy distribution (SED)
can be informative about the average physical conditions in the blazar radiation zone, the time
domain of blazar models has not been adequately explored. The association of high-energy
neutrinos from active galaxies has sparked the interest in models invoking the presence of relativistic
protons in these sources. In this contribution, we explore relativistic proton (hadronic)
signatures in the time domain blazar emission and search for those parameter combinations
that unveil their presence during flaring epochs.
We investigate the time domain of a broad blazar sample. Utilizing the Gaussian process
modeling method of the celerite2 code, we model the parameters of stochastically-driven
damped simple harmonic oscillators. These parameters enable us to create synthetic light
curves describing the high-energy band of each source, thereby motivating the generation of
time series for key model parameters. In particular, we investigate time variations of the
particle energy injection rate, the magnetic field strength, and power law index variations of
the lepto(-hadronic) particle population.
To conduct this SED model exploration we choose the TeV blazar Mrk 501 as our test case,
as it has been the study ground for extensive investigations during individual flaring events.
Using the code LeHaMoC we compute the electromagnetic radiation for a period of several years
that contains several flares of interest. We search for energy windows where the hadronic
emission may dominate, while discussing time lags and flux-flux correlations between different
energy bands. Finally, we provide light curve predictions of Mrk 501 for the upcoming CTAO
with Gammapy.
Main subject category:
Science
Keywords:
Astrophysics, gamma-rays, AGN, Blazars, Time-Series
